The present invention relates generally to testing electronic products, and more particularly to a wide-band tapered-slot antenna and its use in testing wireless radio frequency (RF) devices.
The electronics marketplace is experiencing tremendous growth in the wireless area. Mobile phones, once a luxury referred to as “car phones,” are now ubiquitous. Wireless PDAs, laptops, routers, switches, hubs, and network interface cards are popular.
Like most products, these are tested to ensure that when a consumer makes a purchase, the unit works properly. The goal of testing is to ship every “good” unit, and reject every “bad” unit manufactured. The percentage of good units is the yield. A bad unit may be nonfunctioning, or may not perform as well as its designers intend. Each bad unit shipped costs the manufacturer in terms of customer satisfaction, brand loyalty, and goodwill. Each good unit not shipped may mean that it is retested or replaced, or that a sale is lost.
An example of a wireless product that is tested is mobile phones. In some test systems, a phone is placed in a test box, connected to a test system using a system connector and back plug cable, and various parameters are measured. Based on these measurements, the phone is rejected as bad or passed as good. Unfortunately, in a manufacturing environment, there are variations in readings from one box, as well as among boxes. These variations reduce yield and lower quality control. Also, the back plug cable connectors tend to wear out, and require replacing.
Moreover, each phone requires its own fixture, such that when a different phone is to be tested, the test boxes must be swapped. The new boxes then need to be calibrated. The time needed to install and adjust the new boxes adds to a phone's cost.
Thus, it is desirable to have methods and apparatus for testing wireless devices that reduce variations in measurements, eliminate the need to change test boxes, and eliminate the need for a back plug.